Kevin Spacey delivers the 2013 MacTaggart lecture at the Guardian Edinburgh International Television festival. Photograph: Murdo Macleod for the Guardian

At the same time as Kevin Spacey was telling TV executives to embrace online or die at the annual industry gathering in Edinburgh, a combined audience of 12 million viewers was settling down at home to watch ITV's Emmerdale and EastEnders on BBC1.

Those millions of soap fans could be forgiven for thinking the technological revolution espoused by the Hollywood star had passed them by (when in fact, it is just beginning). There was no shortage of warmth in Edinburgh for Spacey's sentiments. If anyone can deliver a winning speech, it's a double Oscar winner, but the backlash was not long in coming.

Figures released the following day revealed that mobile viewing on iPads, smartphones and laptops still has only niche appeal, accounting for an average of three minutes and 30 seconds a day, compared with the four hours we still spend in front of a TV set.

Traditional TV channels still account for the vast majority of viewing, with 90% of people watching programmes as they are broadcast.

The most talked about show of 2013 is the murder mystery drama Broadchurch, which helped earn ITV the accolade of channel of the year at last week's Guardian Edinburgh International Television festival. It was strictly of the old school variety, broadcast in eight, one-hour instalments on a Monday night.

Not for ITV the binge-watching "all you can eat" tactics of the online TV service Netflix, embraced by Spacey and home to his acclaimed $100m drama remake, House of Cards, the second series of which is currently in production.

"In a way Broadchurch was very against modern trends and, if you like, House of Cards, Netflix [and] bingeing on something," said ITV's director of television, Peter Fincham.

"It reminded us of the deferred pleasure that we had to wait until Monday night. It became a talking point because we waited until Monday night. I think there is a pleasure in that as well.

"I believe if we look into the future I'm an absolute believer in box sets and binge viewing and watching TV in the way you want to. But I also am a very strong believer in the value of the linear schedule, the social value. That's what makes it watercooler television."

In some ways Broadchurch - an unusual drama for ITV in many respects, with its focus on a single murder over the course of an entire eight-part series - reflected Spacey's call for more creative risk-taking, as did Fincham's decision to commission a second series of his sitcom Vicious despite poor ratings.

"When you come to the fundamentals, the appetite of audiences for storytelling and bold storytelling, I thought he was saying the right thing," said Fincham. "Audiences are demanding all of us to raise our game. To be more innovative and challenging."

But there is a balance to be struck, said the BBC's creative director, Alan Yentob. Spacey told TV commissioning editors to "let the talent do what they do, trust the talent".

Yentob told the festival: "[What] we ought to be able to do is enable creativity. That is what leadership is about. The question of how creatives are looked after is not total abandon."

The growth of US-based Netflix in the UK has been exponential, with an estimated 1.5 million paying subscribers since its launch in January last year. Its worldwide customer base is 38 million. But it has never published ratings figures, so exactly how many people are watching its shows - which also include US drama hit Breaking Bad - remain a mystery.

Danny Cohen, the former BBC1 controller who was recently appointed the corporation's director of television, said: "My view is that it is incredibly difficult to be too black or white about this. At least for the next few years there will be a hybrid model where linear TV channels remain very powerful.

"People have had broadband connections for quite a long time now, but live TV viewing remains incredibly popular. On-demand will grow, but the attraction of live TV on a large screen in your living room with your family around you isn't suddenly going to disappear."

Cohen said broadcasters are now in a "battle for screen time", not just with each other but with social media such as Facebook.

"I don't fully agree [with Spacey]," he added. "On-demand is exciting, and we are proud of the strength of the iPlayer, but we know and are very clear that most television is consumed on channels, watched live."

The BBC will launch its most high-profile on-demand experiment yet with the new Peter Kay sitcom Car Share, which will be available in its entirety on the iPlayer, the BBC's online on-demand service, before it appears on television.

Tess Alps, the executive chair of television industry marketing body Thinkbox, which published the latest viewing figures, said: "I think your average viewer is not at all conscious of technology when they have got their Sky HD box and they download Downton Abbey from the ITV Player.

"In their heads they don't think 'I'm using the internet to download TV'. They do it instinctively. We have got to stop thinking of the internet as an enemy. There is lots of technology out there to get stuff to people. The thing that is rare and precious is content."